WFRF:(Crosta M.)
Search: WFRF:(Crosta M.) > (2018) > Gaia Data Release 2...
- 8 of 8
- Previous record
- Next record
- To hitlist
Gaia Data Release 2 : The astrometric solution
-
- Lindegren, L. (author)
- Lund University,Lunds universitet,Astronomi - Genomgår omorganisation,Institutionen för astronomi och teoretisk fysik - Genomgår omorganisation,Naturvetenskapliga fakulteten,Lund Observatory - Undergoing reorganization,Department of Astronomy and Theoretical Physics - Undergoing reorganization,Faculty of Science
-
- Hernández, J. (author)
- European Space Astronomy Centre
-
- Bombrun, A. (author)
- European Space Astronomy Centre
- show more...
- show less...
- (creator_code:org_t)
- 2018-08-10
- 2018
- English.
- In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 616
- Journal article (peer-reviewed)
Abstract
Subject headings
Close
- Context. Gaia Data Release 2 (Gaia DR2) contains results for 1693 million sources in the magnitude range 3 to 21 based on observations collected by the European Space Agency Gaia satellite during the first 22 months of its operational phase. Aims. We describe the input data, models, and processing used for the astrometric content of Gaia DR2, and the validation of these resultsperformed within the astrometry task. Methods. Some 320 billion centroid positions from the pre-processed astrometric CCD observations were used to estimate the five astrometric parameters (positions, parallaxes, and proper motions) for 1332 million sources, and approximate positions at the reference epoch J2015.5 for an additional 361 million mostly faint sources. These data were calculated in two steps. First, the satellite attitude and the astrometric calibration parameters of the CCDs were obtained in an astrometric global iterative solution for 16 million selected sources, using about 1% of the input data. This primary solution was tied to the extragalactic International Celestial Reference System (ICRS) by means of quasars. The resulting attitude and calibration were then used to calculate the astrometric parameters of all the sources. Special validation solutions were used to characterise the random and systematic errors in parallax and proper motion. Results. For the sources with five-parameter astrometric solutions, the median uncertainty in parallax and position at the reference epoch J2015.5 is about 0.04 mas for bright (G < 14 mag) sources, 0.1 mas at G = 17 mag, and 0.7 masat G = 20 mag. In the proper motion components the corresponding uncertainties are 0.05, 0.2, and 1.2 mas yr-1, respectively.The optical reference frame defined by Gaia DR2 is aligned with ICRS and is non-rotating with respect to the quasars to within 0.15 mas yr-1. From the quasars and validation solutions we estimate that systematics in the parallaxes depending on position, magnitude, and colour are generally below 0.1 mas, but the parallaxes are on the whole too small by about 0.03 mas. Significant spatial correlations of up to 0.04 mas in parallax and 0.07 mas yr-1 in proper motion are seen on small (< 1 deg) and intermediate (20 deg) angular scales. Important statistics and information for the users of the Gaia DR2 astrometry are given in the appendices.
Subject headings
- NATURVETENSKAP -- Fysik -- Astronomi, astrofysik och kosmologi (hsv//swe)
- NATURAL SCIENCES -- Physical Sciences -- Astronomy, Astrophysics and Cosmology (hsv//eng)
Keyword
- Astrometry
- Methods: data analysis
- Parallaxes
- Proper motions
- Reference systems
- Space vehicles: instruments
Publication and Content Type
- art (subject category)
- ref (subject category)
Find in a library
- Astronomy and Astrophysics (Search for host publication in LIBRIS)
To the university's database
- 8 of 8
- Previous record
- Next record
- To hitlist
Find more in SwePub
- By the author/editor
- Lindegren, L.
- Hernández, J.
- Bombrun, A.
- Klioner, S.
- Bastian, U.
- Ramos-Lerate, M.
- show more...
- De Torres, A.
- Steidelmöller, H ...
- Stephenson, C.
- Hobbs, D.
- Lammers, U.
- Biermann, M.
- Geyer, R.
- Hilger, T.
- Michalik, D.
- Stampa, U.
- McMillan, P. J.
- Castañeda, J.
- Clotet, M.
- Comoretto, G.
- Davidson, M.
- Fabricius, C.
- Gracia, G.
- Hambly, N. C.
- Hutton, A.
- Mora, A.
- Portell, J.
- Van Leeuwen, F.
- Abbas, U.
- Abreu, A.
- Altmann, M.
- Andrei, A.
- Anglada, E.
- Balaguer-Núñez, ...
- Barache, C.
- Becciani, U.
- Bertone, S.
- Bianchi, L.
- Bouquillon, S.
- Bourda, G.
- Brösemeister, T.
- Bucciarelli, B.
- Busonero, D.
- Buzzi, R.
- Cancelliere, R.
- Carlucci, T.
- Charlot, P.
- Cheek, N.
- Crosta, M.
- Crowley, C.
- show less...
- About the subject
-
- NATURAL SCIENCES
- NATURAL SCIENCES
- and Physical Science ...
- and Astronomy Astrop ...
- Articles in the publication
- Astronomy and As ...
- By the university
- Lund University
Search outside SwePub
- Extend your search to:
- Google Book Search
- Google Scholar
Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.
- Copyright © LIBRIS - National Library Systems
- LIBRIS.kb.se
